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Random bred Merino ram and ewe lambs were vaccinated at 1, 2 and/or 3 months of age with irradiated T. colubriformis larvae. An exponentially increasing challenge of normal larvae was given to all groups including unvaccinated controls commencing at 1 month of age. The results, based on faecal egg counts, showed a dissociation into animals which responded to vaccination (geometric mean egg count 441) and those which did not (geometric mean egg count 1567). The proportion of responders was greatest in groups first vaccinated at the earliest age (1 month). Wool growth and liveweight gains showed severe depression corresponding to peak egg counts, however, responders were less affected than non-responders. There was no correlation between haemoglobin type and resistance to challenge. Faecal egg counts after impulse challenge with 10,000 normal larvae given at about 6 months of age showed a significant ranked correlation with those obtained during the primary exponential challenge. These results confirm that a proportion of young lambs respond to vaccination with irradiated larvae, and that genetically-determined factors are implicated in the ability of animals to respond to vaccination at an early age. 相似文献
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Studies were performed to investigate the effects of the immunosuppressive chemical TCDD. Fetal and neonatal rats were exposed to TCDD through maternal dosing (5 μg/Kg) at Day 18 of gestation and on Days 0, 7, and 14 of postnatal life. Another group of neonatal rats were exposed to TCDD through maternal dosing on Days 0, 7, and 14 of postnatal life only. Parameters of cell-mediated and humoral immune function were investgiated. TCDD suppressed delayed hypersensitivity responses and responses to the mitogens Con A and PHA without affecting humoral immune function. Suppression of T-cell function was selective in that helper function was not suppressed. Transfer of primed T-lymphocytes from TCDD treated and non-treated animals into neonatally thymectomized animals confirmed this. Results indicate that delayed hypersensitivity function and helper function reside in distinct T-cell subsets. 相似文献
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《Saudi Journal of Biological Sciences》2020,27(6):1538-1552
Lead (Pb) toxicity affects the hepatic and renal systems resulting to homeostasis imbalance. Curcumin is a strong antioxidant but has restrained clinical applications due to its poor bioavailability. Nanomedicine showed promising potentials in drug delivery and has brought forth the use of cockle shell-derived aragonite calcium carbonate nanoparticles (CSCaCO3NP) to enhance the effectiveness and targeted delivery of curcumin (Cur). Thus, this study aimed at evaluating the therapeutic effect of curcumin-loaded CSCaCO3NP (Cur- CSCaCO3NP) on lead-induced hepato-renal toxicity in rats. Thirty-six male adults Sprague-Dawley rats were randomly assigned into five groups. All groups contained six rats each except for group A, which contained 12 rats. All rats apart from the rats in group A (control) were orally administered a flat dose of 50 mg/kg of lead for four weeks. Six rats from group A and B were euthanized after four weeks of lead induction. Oral administration of curcumin (100 mg/kg) for group C and Cur-CSCaCO3NP (50 and 100 mg/kg) for groups D and E respectively, commenced immediately after 4 weeks of lead induction which lasted for 4 weeks. All rats were euthanized at the 8th week of the experiment. Further, biochemical, histological and hematological analysis were performed. The findings revealed a biochemical, hematological and histological changes in lead-induced rats. However, treatments with the Cur-CSCaCO3NP and free curcumin reversed the aforementioned changes. Although, Cur-CSCaCO3NP presented better therapeutic effects on lead-induced toxicity in rats when compared to free curcumin as there was significant improvements in hematological, biochemical and histological changes which is parallel with attenuation of oxidative stress. The findings of the current study hold great prospects for Cur-CSCaCO3NP as a novel approach for effective oral treatment of lead-induced hepato-renal impairments. 相似文献
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目的:探讨小儿肺热咳喘口服液联合三联吸入雾化治疗方案对哮喘患儿的治疗效果以及对肺功能的影响作用。方法:将我院自2017年1月至2018年11月间收治的哮喘患儿210例作为研究对象,按照随机数字表法分为两组各105例,研究组患儿在布地奈德、沙丁胺醇、异丙托溴铵三联吸入雾化治疗的基础上给予小儿肺热咳喘口服液进行治疗,对照组患儿仅给予三联雾化吸入治疗,对比观察两组患儿的疗效和预后。结果:研究组临床治疗后总有效率为95.24%,明显高于对照组77.14%(P0.05);治疗后研究组咳嗽消失时间、呼吸困难消失时间和急性发作随诊时间均明显短于对照组(P0.05),两组肺部喘鸣音消失时间比较差异无统计学意义(P0.05);治疗前患儿第一秒用力呼气量(forced expiratory volume in one second,FEV1)、最大肺活量(forced vital capacity,FVC)及FEV1/FVC值、呼气峰流速值(peak expiratory flowrate,PEF)对比无统计学意义(P0.05),治疗后1 d、3 d、7 d以上指标水平均明显升高,且在治疗后7 d,研究组明显高于对照组(P0.05)。治疗期间研究组有1例出现轻度腹泻,3例食欲减退,并发症的发生率为3.81%(4/105),对照组治疗期间2例出现轻度腹泻,4例食欲减退,并发症的发生率为5.71%(6/105),两组比较无统计学意义(P0.05)。结论:使用小儿肺热咳喘口服液联合三联吸入雾化法治疗儿童哮喘急性发作,可改善患儿临床症状和肺功能,疗效显著,可推广使用。 相似文献
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《Journal of Asia》2020,23(4):1130-1137
In Al-Madinah Al-Munawwarah region, Kingdom of Saudi Arabia, Culex pipiens is considered one of the most common mosquitoes. Owing to their exceptional chemical, physical, biological, and eco-friendly properties, ionic liquids (ILs) have been recently considered promising compounds in managing a variety of organisms. Six aminopyridinium-based IL derivatives were assessed to follow their efficacy against adults of C. pipiens. Mosquitoes were treated with aminopyridinium-based IL derivatives either orally or by spraying. It was observed in the first three days of treatment that the accumulated mortality rates were generally higher in sprayed mosquitoes with IL derivatives than their accumulated mortality rates in orally treated mosquitoes with the same ILs. It was also observed that the accumulated mortalities of sprayed mosquitoes at 0.125 and 0.25 g/L were higher than those in mosquitoes orally treated with the same concentrations. The highest mortality rates were 64 and 80% for sprayed and orally treated mosquitoes, respectively. The mode of action of aminopyridinium-based IL derivatives was tracked, and it is demonstrated to be through the digestive route for orally treated mosquitoes. This is the first study to show the adulticidal effects of aminopyridinium-based ILs in controlling C. pipiens. 相似文献
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Ritam Chatterjee Biswajoy Ghosh Mousumi Mandal Debaleena Nawn Satarupa Banerjee Mousumi Pal Ranjan Rashmi Paul Swarnabindu Banerjee Jyotirmoy Chatterjee 《European journal of cell biology》2021,100(1):151146
Oral sub-mucous fibrosis (OSF) is a pathophysiological state of oral cavity or oropharynx having a high chance of conversion to oral squamous cell carcinoma (OSCC). It involves fibrotic transformation of sub-epithelial matrix along with epithelial abnormalities. The present work aims to unveil the mechanistic domain regarding OSF to OSCC conversion exploring the scenario of hypoxia associated oxidative stress, epithelial-mesenchymal transition (EMT), metastasis and stemness acquisition. The study involves histopathological analysis of the diseased condition along with the exploration of oxidative stress status, assessment of mitochondrial condition, immunohistochemical analysis of HIF-1α, E-cadherin, vimentin, ERK, ALDH-1, CD133, Shh, Gli-1 and survivin expressions in the oral epithelial region together with the quantitative approach towards collagen deposition in the sub-epithelial matrix. Oxidative stress was found to be associated with type-II EMT in case of OSF attributing the development of sub-epithelial fibrosis and type-III EMT in case of OSCC favoring malignancy associated metastasis. Moreover, the acquisition of stemness during OSCC can also be correlated with EMT. Alteration of Shh and Gli-1 expression pattern revealed the mechanistic association of hypoxia with the phenotypic plasticity and disease manifestation in case of OSF as well as OSCC. Shh/ Gli-1 signaling can also be correlated with survivin mediated cytoprotective phenomenon under oxidative stress. Overall, the study established the correlative network of hypoxia associated oxidative stress, EMT and manifestation of oral pre-cancerous and cancerous condition in a holistic approach that may throw rays of hope in the therapeutic domain of the concerned diseases. 相似文献